Recently I found out about the standby at my dad's WinXP pc. I'd like to have the standby function for my Gentoo PC (no laptop) too, so I went to Gentoo's Power Management FAQ and started reading.

Since I use dm-crypt and LVM, I'm not able to use swsusp, but I should use swsusp2. So, I downloaded the patches for 2.6.10 kernel, and tried to apply them to linux-2.6.10-gentoo-r5 or linux-2.6.10-hardened-r3, but without succes. This probably is because the Gentoo-kernel was already patched.

So, my question, does anyone knows for which gentoo-kernel these patches work / how you can do this with Gentoo, preferably for x86 2.6.10 kernel?
Did anyone had succes putting his computer to standby / hibernate? Any other suggestions then swsusp2?

I tried
echo standby > /sys/power/state,
but it left my CPU-fan / power-supply-fan running, and it was no full software suspend I think. Sometimes it didn't want to restart after that standby too, but I should test this a bit more. It's however a beginning, since some things in my computer spin down.

I haven't tried it myself, but this howto looks fairly thorough, include kernel patching instructions, etc._________________"One of the major problems encountered in time travel is not that of accidentally becoming your own father or mother ... The major problem is quite simply one of grammar..."

Yes, I'm using swsusp2 happily on my laptop. It has a couple of limitations (glx...) but it's fully worth it not to have to do a full boot each time.
It's definately the way to go - I hear the others need a dedicated partition, whereas swsusp2 does it to swapfile which strikes me as pretty clever.

First: swsusp2 is NOT activated via /sys/power/state. That's a control for the standard ACPI sleep states. Given the current state of ACPI support, echoing anything to one of them probably isn't the best idea...
For example, on my notebook if I echo say "mem" or "disk" to it, it'll power the notebook straight off, which is neat. Unfortunately turning it back on then has basically no effect.

To start, you have to get it into your kernel. You've got three options really:
1) Get a vanilla kernel which it'll patch against fine
2) Get a prepatched kernel (see the Unsupported Software forum and find one you like)
3) Fix the rejects in your current kernel (possibly quite difficult).
I'll leave that choice up to you - I like option 2, but a lot of people find that sort of thing too unstable.

Once you've rebooted to the patched kernel, run "emerge hibernate-script". This will give you the userspace scripts used to kick off a hibernate.

Then run "hibernate" at a shell. It's recommended to try this outside X first, although I've never had any issue getting it going under X.

Finally you may want to bind it to a hotkey; I'll leave that bit up to you, it's been covered elsewhere.